1. Field of the Invention
This invention relates to wire cleaners, which are used to remove surface buildup from metallic wires. Metallic wires include single metals and alloys. For example, nickel/titanium wires may be cleaned with this instant invention. This invention is particularly applicable where a viscous cleaning compound under pressure is used.
2. Description of Related Art
Wire cleaning methods may be chemically based, mechanical (abrasive), or a combination of both. Chemical cleaning methods provide good cleaning uniformity. However, chemical cleaning methods require environmental and safety controls. Abrasive systems usually do not. Hence, abrasive systems are often preferred for simplicity of installation and use.
One type of abrasive cleaning method is sand blasting. Sand blasting is effective and aggressive, but surface uniformity of the cleaned wire is marginal.
Another abrasive method is buffing with fine grit wheels. With wheel buffing, wire surface quality is better than sand blasting. But under a microscope a non-uniform herringbone scratch pattern is apparent.
An abrasive nozzle method forces both a viscous cleaning compound and the wire into a prior art nozzle. The cleaning compound enters through the wide end of a cone, which is integrated into the entry end of the nozzle. The cleaning compound exits through an opening in the exit end of the nozzle. The wire to be cleaned travels along the axis of the nozzle. Most of the cleaning occurs where the wire passes through the apex of the cone. High pressure creates close surface contact between the wire and the cleaning compound. Furthermore, the relative velocity between the wire and the cleaning compound is enhanced by turbulent flow of the cleaning compound.
Cleaning results for the abrasive cone method have been satisfactory. But the abrasive cone method, as currently practiced, is not optimal.
In particular, the use of multiple nozzles to create multiple cleaning steps integrated into one pass through the cleaning apparatus has not proven useful. Wire surface quality from experiments with multiple nozzles was roughly the same as the surface quality using a single nozzle.
The reason is the shape of the nozzle. The cleaning compound, which is in close contact with the wire surface, does not change as the wire moves from one nozzle to the next. That is, the prior art nozzle shape does not mix the cleaning compound.
A new nozzle design is needed.